This invention relates in general to steering axles for vehicles and in particular to an improved hydraulic cylinder assembly for use with such a steering axle.
Wheeled vehicles are typically provided with axles for supporting the vehicle frame on a plurality of rotatable wheels. Such axles usually include a fixed housing secured to the vehicle frame and a pair of wheel hubs rotatably carried on the housing. In some axles, the wheel hubs are free wheeling, i.e., not connected to any source of rotational power. In other axles, the wheel hubs are rotatably driven by an engine connected thereto by a plurality of drive train components. In either type of axle, however, it may further be desirable to support the wheel hubs for pivoting movement relative to the axle. This pivoting movement permits the wheel hubs to steer the vehicle in desired directions. Axles of this type are commonly referred to as steering axles.
Many different structures are known for controlling the pivoting movement of the wheel hubs in steering axles. One common structure involves the use of a hydraulic cylinder secured to the axle housing. A piston is disposed within the cylinder for selective axial movement in response to the application of pressurized fluid therein. A steering rod is connected to the piston and extends out the ends of the cylinder. The ends of the steering rod are connected to the wheel hubs such that axial movement of the piston causes pivoting movement of the wheel hubs, thus effecting steering of the vehicle.
For the sake of economy, it is desirable that a single basic steering axle structure be adaptable for use in a plurality of different vehicles. Unfortunately, different vehicles usually have different steering requirements. For example, some vehicles may require a larger range of pivoting movement for the wheel hubs than others. Although hydraulically driven steering axles can and have been used in different vehicles, it has been found to be inconvenient to define the limits of axial movement of the piston within the cylinder to accommodate these different steering requirements. Thus, it would be desirable to provide such a hydraulically actuated steering axle with a means for quickly and easily defining the limits of axial movement of the piston within the cylinder to accommodate the varying steering requirements of different vehicles.